Access RMAN Backups of Old Oracle Incarnations

Quick Tip

When you need to access an old backup but the current database has been changed, duplicated or restored with resetlogs, you have to tell RMAN the exact previous DBID and Incarnation from the time the backup was taken.

Access Old Backup

To setup RMAN to access old backups follow these steps:

  • Get the DBID and Incarnation using command list incarnation of database
  • Set the database id using command set dbid
  • Set the incarnation using command reset database to incarnation

First get the list of incarnations:

RMAN> list incarnation of database ;

List of Database Incarnations
DB Key  Inc Key DB Name  DB ID            STATUS  Reset SCN  Reset Time
------- ------- -------- ---------------- --- ---------- ----------
77793547 77818648 PATODB  1380000018       PARENT  9460880553691 20-OCT-19
77793547 77793548 PATODB  1380000018       CURRENT 9460880687987 21-OCT-19
82721833 82723417 PATODB  1393720406       PARENT  9391138077038 03-MAR-20
82721833 82721834 PATODB  1393720406       CURRENT 9556600865638 24-MAR-20

As we want to restore a backup from February 2020 we need to point to the database id 1380000018 and the incarnation 77793548:

RMAN> set dbid=1380000018

executing command: SET DBID
database name is "PATODB" and DBID is 1380000018

RMAN> reset database to incarnation 77793548 ;

RMAN> list backup of database;

And that’s it, we can access now backups generated in the time frame of that combination of DBID and Incarnation.